Sealing device with improved adhesion

Abstract

The present invention relates to a sealing device ( 1 ) comprising a barrier layer ( 2 ) and an adhesive layer ( 3 ), and which is suitable for sealing bases in the building sector. The adhesive layer comprises a polymer P2, the polymer P2 being polyethylene (PE), polypropylene (PP) or a copolymer of ethylene and propylene, and a polyolefin-based polymer P3, the polymer P3 having at least one functional group which is selected from the group consisting of carboxylic acids, OH-groups, anhydrides, acetates and glycidyl methacrylate, and azo-dicarbonamide A. The invention further relates to a method for sealing the said bases. The method according to the invention allows structures of civil engineering to be sealed rapidly and efficiently and ensures good adhesion of the sealing device on the base.

The invention claimed is: 
     
       1. A sealing device, comprising:
 a sealing layer, comprising: a thermoplastic polymer; and 
 an adhesive layer, comprising:
 a first polymer that is a polyethylene, a polypropylene or a copolymer of ethylene and propylene; 
 a second polymer that is a polyolefin-based polymer comprising at least one functional group selected from the group consisting of a carboxylic acid, a OH group, an anhydride, an acetate, and a glycidyl methacrylate; and 
 azodicarbonamide A; 
 wherein: the adhesive layer includes from 0 to 0.5 wt % of an epoxy resin. 
 
 
     
     
       2. The sealing device of  claim 1 , wherein the second polymer is selected from the group consisting of:
 a maleic anhydride-functionalized polyethylene; 
 a maleic anhydride-functionalized polypropylene; 
 a maleic anhydride-functionalized copolymer of ethylene and propylene; 
 an ethylene vinyl acetate copolymer functionalized with maleic anhydride; 
 an ethylene vinyl acetate copolymer; 
 a glycidyl methacrylate-functionalized polyethylene; and 
 an ethylene acrylic acid copolymer. 
 
     
     
       3. The sealing device of  claim 1 , wherein the second polymer is:
 a maleic anhydride-functionalized polyethylene; 
 a maleic anhydride-functionalized polypropylene, or 
 a maleic anhydride-functionalized copolymer of ethylene and propylene. 
 
     
     
       4. The sealing device of  claim 1 , wherein a content of the second polymer in the adhesive layer is from 1 wt % to 18 wt %. 
     
     
       5. The sealing device of  claim 1 , wherein a content of the second polymer in the adhesive layer is from 2.5 wt % to 15 wt %. 
     
     
       6. The sealing device of  claim 1 , wherein a content of the second polymer in the adhesive layer is from 5 wt % to 12 wt %. 
     
     
       7. The sealing device of  claim 1 , wherein a ratio of azodicarbonamide A to the second polymer is from 0.1 to 1.2. 
     
     
       8. The sealing device of  claim 6 , wherein a content of azodicarbonamide A in the adhesive layer is from 3 to 7% by weight. 
     
     
       9. The sealing device of  claim 1 , wherein the second polymer is a maleic anhydride-functionalized polyethylene that is a maleic anhydride-functionalized low density polyethylene, or a maleic anhydride-functionalized high density polyethylene. 
     
     
       10. The sealing device of  claim 5 , wherein a content of azodicarbonamide A in the adhesive layer is from 0.5 wt % to 5 wt %. 
     
     
       11. The sealing device of  claim 1 , wherein the adhesive layer is free of an epoxy functionality. 
     
     
       12. The sealing device of  claim 1 , wherein the adhesive layer is tack-free at 23° C. 
     
     
       13. A method for sealing a substrate, the method comprising:
 applying the sealing device of  claim 1  to a substrate, wherein the adhesive layer of the sealing device faces the substrate; and 
 heating the adhesive layer. 
 
     
     
       14. The method of  claim 13  further comprising applying a second substrate to the sealing layer of the sealing device. 
     
     
       15. The method according to  claim 14 , wherein the second substrate is asphalt. 
     
     
       16. A shaped body comprising the sealing device of  claim 1 ,
 wherein the shaped body is firmly bonded to the adhesive layer of the sealing device. 
 
     
     
       17. A sealing base comprising the sealing device of  claim 1 .